Medium density fiberboard, or MDF, is a sheet of wood that has been manufactured. MDF has a lower cost than many types of hardwood lumber. It is considered a green product since it is made of waste materials and does not require fresh timber. MDF provides consistency throughout the board and is not susceptible to splintering. Medium density fiberboard does have some disadvantages in comparison to wood, including a higher weight per inch, less strength and the inability to repel moisture and a lack of wood grain. The lack of grain poses a problem for some cabinetmakers, since it means that the boards will need to be primed and painted. The material is too absorbent for stains and will not have the finished look of wood.